A noise cancelling system that provides a satisfactory music playback environment for a listener (user) by reducing (cancelling) ambient noise (noise) in the external environment when the listener listens to music or the like through earphones, headphones, or the like is known. In one example, Patent Literature 1 discloses a twin-type ambient noise cancellation device in which a feedback-based noise cancelling technique using a microphone installed in the inside of a casing and a feedforward-based noise cancelling technique using a microphone installed on the outside of the casing are integrated.